Grouting tool



Jan- 19 1965 T. P. LENAHAN r-:TAL

GRou'rING Toor.

Filed June 22, 1961 HG2 H64 M A TTORNE Ys United States Patent O3,166,132 GRQU'HNG TOOL v Thomas P. Lenahan, Billie .lack Bradley, andAllen H. Limbaugh, Duncan, Okia., assignors. to Halliburton Company,Duncan, Okla., a corporation of Delaware Filed June 22, 1961, Ser. No.118,850 7 Claims. (Cl. 17E-235) This invention relates to a method andapparatus for grouting unconsolidated formations and, more particularly,to a method and apparatus for drilling a hole and injecting groutingmaterial to consolidate the soil around the drill hole. y

One method for improving the load bearing characteristics of subsoilcontaining substantial quantities of sand, clay or gravel is to permeatethe subsoil with groutto form a large, solid mass which is capable ofwithstanding heavy loads. The large mass of consolidated soil alsoprevents lateral slippage, for example, on hillsides.

The usual method of grouting is to drive a pipe into the soil by pumpingwater down through the pipe and out through a nozzle mounted on the endof the pipe. The stream of Water issuing from the nozzle washes away theearth and the pipe falls downward into the resulting cavity. When thebottom of the pipe has reached the desired depth, the ow of Water isstopped and grouting material is then pumped through the pipe and outatthe bottom, permeating the surrounding soil. When it has hardened, theconsolidated earth forms a foundation which has increased bearingstrength and is resistant to lateral slippage.

V.The grouting tools heretofore proposed have several limitations. Sinceal1 of the grouting material must be forced through the jet at thebottom of the pipe, it takes a considerable amount of time to inject thegrouting material into the bore hole. The penetration and distributionof the grouting material, also, is extremely limited since it isinjectedat a single point. i

'Attempts have been made to improve the distribution of grout in thedrill hole by using compound pipe. The inner pipe conducts water fordrilling and the outer pipe, which is provided with holes along itslength, distributes grouting material. This method is not practical,however, since compound pipe is heavy and expensive.

Accordingly, it is an object of this invention to provide a method andapparatus for uniformly distributing grout in a bore hole. y v

It is a further object of this invention to provide a grouting toolwhich permits the rapid injection of grout in a bore hole.

Another object of this invention is to provide a grouting tool which isadapted to be mounted on standard drill pipe.

In accordance with a preferred embodiment of this invention, thegrouting tool has a easing which is secured to a length of pipe. Anozzle is secured to the bottom ice pumped into the pipe it flowsoutward through the screen vand longitudinal slots. This permits ahigher rate of flow of thegrouting material than is possible through thejet and results in a larger distribution of the grouting material alongthe length of the bore hole.

This preferred embodiment ofthe invention is illustrated in theaccompanying drawings, in which:

FIGURE 1V is an elevational view of a grouting tool suspended in a borehole. A

FIGURE 2 is a cross sectional view of the grcuting tool. A

FIGURE 3 is a cross sectional view of the lower'portion of the groutingtool showing the tool during a drilling operation.

FIGURE 4 is a cross sectional view of the upper portion of the groutingtool showing a sinker bar and snap ring in engagement with the tube. V

FIGURE 5 is a cross section-al View of the grouting tool showing thetool during grouting.

In accordance with a preferred embodiment of the invention, referring toFIGURES 1 and 2, a casing 1 is threadably secured to a well pipeZ bymeans of a connector 3. The casing 1 is provided with a plurality oflongitudinal slots 4 spaced around the circumference of the pipe. Atubular screenV 5 is secured to the interior of the casing and extendsalong the length of the slots 4L The screen 5 is a composite, water-welltype screen'with a layer of heavy mesh screen adjacent the slots and -alayer of iine mesh screen adjacent the interior of the casing 1. Themesh of theV screen is suiiiciently line to prevent sand or soil fromthe well bore from entering the casing 1 but not fine enough to preventthe liowA of grout outward through the screen 5. v

A valve body 6 is threadably secured to the lower end of the casing 1.The valve body 6 is provided with a central bore 7 which communicateswith the interior of the casing 1. An enlarged portion of the bore 7forms a seat 8 for a tube 9 which is telescoped within the casingnl andconnector 3. The tube 9 has substantially the same outer diameter as theinner diameter of the connector 3. O-rings 10 and 11 mounted on the tube9 cooperate with the connector 34 and valve body 6, respectively, toform a seal to'prevent the ow of uid into the space between the interiorof the casing 1 and the outside of tlie tubeV 9;

A nozzle 12 is threadably secured to the lower end of the valve body 6.The interior of the nozzle 12 and the g lower portion of the valve body6 form a cage for a ball 1 base 14 by the legs of the base which extendthrough the of the casing and longitudinal slots are provided around ithe circumference of the casing above the nozzle. A screen is mounted onthe inside of the pipe'adjacent to the slots. A removable tube ismounted within the casing to block the ow of Huid through the slotsinthe casing. The tool is held in a vertical position and water ispumped through the nozzle to drill a hole forthe pipe. When the desireddepth is reached, the ow of water is stopped and asinker bar with a snapring on its nose is run down the pipe to retrieve the tube. The upperend of the tube is provided with an interior iiange which is engaged bythe snap ring to facilitate removal of the tube. A ball is then droppedinto the pipe to rest on a seat above the nozzle to prevent groutingmaterial from flowing out through the nozzle. When the grouting materialis slots 17 in the tube. vA ball 18 is secured to the opposite end ofthe tube 16 and a spring 19, which is confined within the tube 16,exerts a force on the base 14 to' urge the ball against a seat 20 in thevalve body 6. The spring closes the` valve 13 to prevent fluid fromilowing back into the casing 1 through the nozzle 12 when there is nodrill iiuidflowing through the bore 7. The lower end of the nozzle 12 isprovided withV an'orice 21`to permit fluid to ow out through the end ofthe pipe.

The interior of the tube 9 is provided With a cylindrical recessVportion 22 of an Venlarged diameter. The top of the cylindrical recessportion 22 forms an internal ange 23. The interior of the tube 9 issufficiently large ito permit a sinker bar 24 to be inserted into thetube, as shown in FIGUREA. The sinker Vbar 24 isk provided with a snapring 25. The ysnap ring is compressed by. a tapered portion 26 at thetop of the tube 9 and Vthe snap ring 25 expands when it enters thecylindrical recess portion 2v2.

l As the sinker bar 24 is raised, the snap ring 25 engages Patented Jan.19, 1965 is necessary to block the bore 7. "This is accomplished,

as shown in FIGURE 5, by'dropping a ball 27 down Vthrough the pipe 2.The ball is large enough to become lodged on the seat 8 of the valvebody 6,thereby .acting as a valve to prevent grout from owing out:through the bore 7.` Y

In, operation, the tool is assembled as shown in FIG- URE 2 and a hose28 is attached to the top of the pipe 2. Water, or other drill huid, ispumped through 'a hose 28, into the pipe2 and through the casing-1. The-pres' sure of the water on the ball 18 causes the check valve 13 toopen, permitting the water to ow through the nozzle 12 and outvof thebottom of the pipe through the ori- The stream of water issuing from thenozzle 12 washes away the soil at the bottom of Vthe hole, forces it upalong the sidesl of the casing 1 and out at the top of the hole, asshown in FlGURE 1. The screens 5 prevent sand from entering the casingand from becoming packed around the tube 9. An accumulation of sand ordebris between the casing 1 and the tube 9 is undesirable, since itmight form an obstructionto the removal of the tube 9. At this timethere is no ow of WaterV through the slots 4 since O-rings 10y and 11 onthe tube 9 seal the slots 4 from the interior of the casing 1. Y

When the desired depthk hasbeen reached, the water is shut off and dueto the drop in water pressure the check valve 13 closes. A isinker bar24 with a snapvring on itsnose is run down the pipe 2 .to retrieve thetube 9. After the tube is removed from the pipe, a ball 27 is droppeddown the pipe. The ball lodges on the seat 8 of the valve body 6 toprevent 'the flow of grouting material through the bore 7 of the valvebody. The grouting material is then injected into the pipe andowsfoutw-ard through the screens 5 and the rslots 4 in the ,side

of the casing 1. The valve 13 prevents the Vreturn ow of thegroutingmaterial into the casing through the nozzle 12.

After the grout has been injected in the well bore, the pipe can beremoved from the Well and reused, or it can remain in the well supportedby Ithe consolidated subsoil. Since the exterior surface Yof thegrouting tool Vdoes not have any projections which would resist theremoval K of the tool, it can be easily raised .from the well boreimmediately after the grout has been applied.

There are kseveral advantages in pumping the grouting material throughthe slots in thesidefof the pipe 1 rather than through the nozzle 12.One important advantage is that the flow area through the Vscreen ismuch greater than through the nozzle and the' grouting material can bepressure streamof uid for drilling and injecting groutl over la largearea, sequentially.`

While the invention has beenillustrated and described in one embodiment,it is recognized that variations and changes may be made therein withoutdeparting from the invention as setforth inthe claims.

We claim:

1. Apparatus for drilling wells and forinjectng grout ing materials intounconsolidated subsoil formations comprising a casing, means forsecuring the casing to the end of aconduih said casing having aperturesin the wall thereof, a nozzle secured tothe end of the casing fordirecting a stream of uid downwardly toerode theV soil beneath -thepipe, valve means in the nozzle, a tube telescoped within the casing iniuid sealing relation across said apertures, means for removing thetube, and means for shutting otf outward fiow of fluid through thenozzle when the tube is removed.

V2. Apparatus for drilling wells and for injecting grouting `materialsinto unconsolidated subsoil formations comprising a casing, means forsecung the casing to the end of a conduit, said casing havinglongitudinal,

slots extending through the wall thereof, a screen secured to the insideof the casing over the slots, a nozzle secured to the end of the casingfor directing a stream of tluid downwardly to erode the soil beneath thepipe, a sleeve valve mounted in the casing for preventing ow of fluidthrough the' slots, a check valve in the nozzle for.pre venting reverseilow of uidfrom the nozzle to the casing and means for'opening thesleevevalve.

f 3. Apparatus for drilling wells and for injecting grout- .Y ingmaterials into unconsolidated subsoil formations ,j to the end of thecasing for directing a stream of iluid downwardly to erode the soilbeneath the pipe, a sleeve valve mounted in the casing for preventingflow of fluid through the slots, said casing having a valve seat thereinforV engagement by the sleeve valve, a check valve inv the nozzle forpreventing reverse flow of iluid from the nozzle to the casing and meansfor opening Athe sleeve valve.

4. Apparatus for drilling wells and for injecting grouting materialsinto unconsolidated subsoil formations comprising a'casing, means forsecuring said casing to the end of a conduit, said casing havinglongitudinal slots extending through the wall thereof, a screen securedto the inside of the casing over'the slots, a nozzle secured to the endof the casing for directing a stream ofV uid downwardly to erode thesoil beneath the pipe,.a sleeve valve mounted in the casing Kforpreventing ow of fluid through the slots, a check valve in the nozzlefor preventing reverse ow of lluid from the nozzle to the casing, meansfor opening the sleeve valve and'means for selectively blocking llow` offluid from the casing through the nozzle whereby after the sleeve isopened, fluid is directed from the casing through the slots.

Y 5. lApparatus for drilling wells and for injecting grout ing materialsinto unconsolidated subsoil formations comprising a casing, means for:securing said casing to the end of a conduit, said casing havinglongitudinal slots extending through the wall thereof, a screen securedto the inside of the casing over the slots, a nozzle secured to theendof the casing for directing a stream ofuid downwardly to erode the soilbeneath the pipe, said casing having a valve seat therein, a tubetelescoped in the casing and extending along the slots, sealing meansbetween the tube and the casing for preventing fluid flow from thecasing through the slots, said tube engaging the valve seat, aV checkvalve in the nozzle for. preventing reverse flow of fluid from thenozzle to the casing and means for removing the tube from the casing.

n 6. Apparatus for drilling wells and for injecting groutlng materialsinto unconsolidated subsoil formations comprlslng a casing, means forsecuring said casing to the end of a conduit, said casing havinglongitudinal slots extending through the wall thereof, a screen securedto the inside of the casing over the slots, a nozzle secured to the endof the casing for directing a stream of iiuid downwardly to erode thesoil beneath the'pipe, said casing having a valve seat therein, a tubetelescoped in the casing and extending along the slots, sealing meansbetween the tube and the casing for preventing fluid flow from thecasing through the slots, said tube engaging the valve seat, a checkvalve in the nozzle `for preventing reverse ow of fluid from the nozzleto the casing, means for removing the tube from the casing and a plugcooperating with the valve seat to block the ow of uid from the casingthrough the nozzle after the tube is removed.

7. Apparatus for drilling Wells and for injecting grouting materialsinto unconsolidated subsoil formations comprising'a casing, means forsecuring the casing to the end of a conduit, said casing havingapertures in the Wall thereof, a nozzle secured to the end of the easingfor directing a stream of Huid downwardly to erode the soil beneath thepipe, one-Way Valve means for allowing fluid iioW out of the nozzle, butpreventing liuid flow into the casing through the nozzle, meansextending across the apertures in fluid sealing relation with thecasing,

means for selectively removing the sealing means to per: mit fluid ilowthrough the apertures, and meansV for 15 2,924,948

shutting olf outward oW of i'luid through the nozzle after the sealingmeans is removed. Y

References Cited in the le of this patent UNTED STATES PATENTSw 277,695Edson Mayk 15, 1883 1,279,783 Stirling Sept. 24, 1918 1,449,672Hallvarson Mar. 27, 1923 2,185,522 Rollins Jan. 2, 1940 2,321,318Reist'le ,Iune 8, 1943 2,387,602 Bannister Oct. 16, 1945 2,774,569Jacobsen .De'c. 18, '1956 2,785,875 Hayes Mar. 19, 1957 2,890,169 ProkopJune 9, ,1959

Mueller Feb. 16, 1960v

1. APPARATUS FOR DRILLING WELLS AND FOR INJECTING GROUTING MATERIALSINTO UNCONSOLIDATED SUBSOIL FORMATIONS COMPRISING A CASING, MEANS FORSECURING THE CASING TO THE END OF A CONDUIT, SAID CASING HAVINGAPERTURES IN THE WALL THEREOF, A NOZZLE SECURED TO THE END OF THE CASINGFOR DIRECTING A STREAM OF FLUID DOWNWARDLY TO ERODE THE SOIL BENEATH THEPIPE, VALVE MEANS IN THE NOZZLE, A TUBE TELESCOPED WITHIN THE CASING INFLUID SEALING RELATION ACROSS SAID APERTURES, MEANS FOR REMOVING THETUBE, AND MEANS FOR SHUTTING OFF OUTWARD FLOW OF FLUID THROUGH THENOZZLE WHEN THE TUBE IS REMOVED.